I broke up with neovim....vim is my best friend now

dot_vim/plugged/vimtex/test/test-parser-cmds/Makefile

@@ -0,0 +1,9 @@
+.PHONY: test
+
+MYVIM ?= nvim --clean --headless
+
+INMAKE := 1
+export INMAKE
+
+test:
+	@$(MYVIM) -u test.vim 2>&1

dot_vim/plugged/vimtex/test/test-parser-cmds/test.tex

@@ -0,0 +1 @@
+% crash if there is \begin in comment

dot_vim/plugged/vimtex/test/test-parser-cmds/test.vim

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+set nocompatible
+let &rtp = '../..,' . &rtp
+filetype plugin on
+
+nnoremap q :qall!<cr>
+
+silent edit test.tex
+
+if empty($INMAKE) | finish | endif
+
+try
+  let s:cmd = vimtex#cmd#get_next()
+  call assert_equal('\begin', s:cmd.name)
+catch
+  echo 'Failed to parse command!'
+  echo getline('.') "\n"
+  cquit
+endtry
+
+call vimtex#test#finished()